It has been recognized for many years that boosting potentials during active DRAM cycles can enhance reading and writing. See, U.S. Pat. Nos. 4,247,917; 4,087,704; and 4,584,672.
It is also known in DRAMs to level shift signals for a variety of reasons. An example of level shifting is shown in U.S. Pat. No. 4,460,257.